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RM2605   Sulphur and calcite

This is an exceptional sulphur specimen, both for this Russian mine and for the perfection of the crystals. In a cavity of the matrix several very well defined and doubly terminated crystals of sulphur are disposed, clearly showing the dipyramidal faces of different orders. With brilliance, translucent to transparent. With another group of crystals, one of them predominant, on sample side. On a matrix with scalenohedral calcite crystals. Specimens of this mine and with this fine quality are more than difficult to see. A sample from the Astor collection (Barcelona). You can find more information about this locality at geo.web.ru.

Size: 6.6 x 6.5 x 5.2 cm.
Main crystal: 1.4 cm.
Found in ±1998
Col. Joan Astor (Barcelona).
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RM2447   Belomarinaite

Extraordinary translucent laminar specimen of belomarinaite, an extremely rare sodium and potassium sulphate, of good size and with clearly visible crystalline forms. It refers to both chemistry and structure to aphthitalite. These sulfates are formed in saline deposits and in volcanic fumaroles, as is this case. This specimen comes from the type locality for the species. A unique opportunity for systematic collectors.

Size: 2 x 1.2 x 0.1 cm.
Found in ca. 2017.
Ex. M. Murashko specimen.
Type Locality
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RM2444   Alumoåkermanite

Specimen of alumoåkermanite (IMA2008-049) from the pegmatites of the Kola peninsula. Honey coloured. It is probably accompanied by species such as cebollite and juanite those form a whitish vein. A very rare species, very visible in the polished section. Good size. It comes from the southern part of the Kola Peninsula.

Size: 3.5 x 3.1 x 1.9 cm.
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RM2445   Bementite
Mn7Si6O15(OH)8

Bementite is a very rare manganese silicate, identified in the well-known Franklin mine (NJ, USA), where it has its type locality. This specimen comes from a mining area located in the central zone of the Pre-polar Urals, known for the manganese, rhodonite and magnetite mines. In this specimen we can observe aggregates of crystals with golden tones that stand out on the matrix. An opportunity for systematic collectors.

Size: 3.4 x 2.5 x 2.4 cm.
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RM2440   Wadeite and aegirine

Excellent specimen of this rare potassium and zirconium silicate. It shows rich aggregates of hexagonal crystals, transparent to translucent, with an excellent brilliance. Colourless to slightly violet.They are disposed on a matrix of acicular aegirine crystals with a very dark green color, almost black. The Kukisvumchorr Mountains are in the central part of the Khibiny Massif. The area has a very interesting mineralogy, notable for its nepheline syenites.

Size: 4.2 x 3.5 x 2.8 cm.
Main crystal: 3 mm.
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RM2482   Opal
SiO₂·nH₂O
  -  0.

Very glassy opal specimen, with excellent transparency and yellowish bands. From an unusual area of Russia for this variety of quartz. It was acquired by A. Trigo (Mataró) in 1983, in Expominer Mineral Show (Barcelona).

Size: 4.5 x 3.9 x 1.5 cm.
Found in ca. 1983
Col. Antonio Trigo (Mataró).
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RM2484   Calcite (glendonite variety) pseudomorph after ikaite
Ca(CO3)
  -  5. Carbonides and nitrates

Glendonite is the name given to the pseudomorphic calcite after ikaite. Ikaite, a hexahydrated calcium carbonate, was first observed in nature in the 1960s, at the seabed of the Ikka Fjord in Greenland. There, it precipitates due to the mixture of cold water submarine springs (3°C) rich in carbonates with seawater. Ikaite deposits are not usually found due to its poor stability, however, sometimes the rapid conversion of ikaite to calcite and water results in the generation of pseudomorphic calcite aggregates in the shape of the ikaite crystal (so-called glendonites). These calcite pseudomorphs directly replace ikaite above 4ºC.

Size: 6.1 x 2.2 x 1.7 cm.
Found in ca. 1995.
Col. Antonio Trigo (Mataró).
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RM2255   Johillerite

Very interesting blue-violet to lavender aggregates of johillerite, on matrix, and accompanied by black hematite crystals. Johillerite is a extremelly rare arsenate with sodium, copper and magnesium+zinc: Na(Mg,Zn)3Cu(AsO4)3. Only three localities worldwide: Tsumeb (TL), slags from Genna (Germany) and the Tolbachik volcano in Kamchatka. Johillerite forms a continuous solid-solution system with badalovite and nickenichite. Johillerite samples were obtained from the fumaroles of the North Breach of the great fissure Tolbachik volcano eruption (1975-1976). Cone took 44 days to form.

Size: 4.5 x 3.2 x 3 cm.
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RM2256   Shcherbakovite, Schizolite and Lamprophyllite

Aggregate of brown prismatic crystals of this rare niobium and tantalum silicate found in the alkaline pegmatites of the Khibiny Mountains, in this remote area of the Kola Peninsula. It is accompanied by pink aggregates of schizolite, an intermediate member of the pectolite-serandite series, and of lamprophyllite. Identified by Dr. D. Lisitsin.

Size: 5.6 x 3.8 x 2.8 cm.
Main crystal: 1.7 cm.
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RM2228   Lorenzenite

Lorenzenite is a rare sodium titanium silicate found in pegmatites and nepheline syenites. A lustrous, sharp, chocolate-brown crystals in matrix on this excellent specimen from the Joan Astor Collection.

Size: 4.5 x 4 x 3 cm.
Main crystal: 1.8 cm.
Found in 1994.
Col. Joan Astor.
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RM2122   Native iron in basalt

Slab of native iron in mafic matrix. Specimen is tilted so reflections of sunlight make iron stand out from matrix. This iron could be refered to kamacite variety (content in Ni, see the apple green tones). It is accompanied by fayalite-forsterite and labradorite. Probably some cohenite is present in the sample. One side polished, natural the other. Analisys will be send to the buyer.

Size: 4.8 x 3.7 x 0.9 cm.
Analyzed specimen with report
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RM2124   Native iron in basalt

Slab of native iron in mafic matrix. Specimen is tilted so reflections of sunlight make iron stand out from matrix. This iron could be refered to kamacite variety (content in Ni). It is accompanied by fayalite-forsterite and labradorite. Probably some cohenite is present in the sample. Both sides polished showing internal structures. Analisys will be send to the buyer.

Size: 4.9 x 3.5 x 0.5 cm.
Analyzed specimen with report
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RM2108   Wiluite

Doubly terminated wiluite floating crystal, a rare calcium, aluminum and magnesium silicate with boron. It presents two prisms of different order, the tetragonal dipyramid truncated by the pinacoid. With a interpenetrated crystal. Good size and deep green colour. Wiluite was accepted as a new species in 1997 belonging to the vesuvianite group. It comes from the type locality for the species.

Size: 2.4 x 2.2 x 1.9 cm.
Type Locality
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RM2125   Wiluite

Doubly terminated wiluite floating crystal, a rare calcium, aluminum and magnesium silicate with boron. It presents two prisms of different order, the tetragonal dipyramid truncated by the pinacoid. really good size and deep green colour. Wiluite was accepted as a new species in 1997 belonging to the vesuvianite group. It comes from the type locality for the species.

Size: 2.6 x 2.3 x 1.7 cm.
Type Locality
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RM2126   Wiluite

Doubly terminated wiluite floating crystal, a rare calcium, aluminum and magnesium silicate with boron. It presents two prisms of different order, the tetragonal dipyramid truncated by the pinacoid. Good size and deep green colour. Wiluite was accepted as a new species in 1997 belonging to the vesuvianite group. It comes from the type locality for the species.

Size: 2.3 x 1.8 x 1.7 cm.
Type Locality
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RM2096   Clinochlore, seraphinite variety
Mg5Al(AlSi3O10)(OH)8

Aesthetic specimen of clinochlore, variety seraphinite, forming nodular masses of radiating crystals. Polished slabs such as this have become popular ornamental items. The varietal name seraphinite refers to Biblical angelic beings having three pairs of wings, and is a trade name referring to the fibrous, silvery crystals that compose it. One side is polished showing the internal structure; the other side is natural with this "curious" label...

Size: 7.2 x 4.8 x 1.5 cm.
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RM2119   Fluorapatite

On a calcite and quartz matrix sits an aesthetic, doubly terminated fluorapatite crystal with this nice blue color, with curious rounded faces and edges. The very glassy luster, translucent, color and size of this specimen make this a fine mineral specimen. This Russian fluorapatite specimens from this locality are highly appreciated for lustre and gemminess. Good size and very aerial disposed.

Size: 4.8 x 4.2 x 3.5 cm.
Main crystal: 4.5 x 2.2 cm.
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RM1895   Native iron in basalt

Slab of native iron in mafic matrix. Specimen is tilted so reflections of sunlight make iron stand out from matrix. This iron could be refered to kamacite variety (content in Ni). It is accompanied by fayalite-forsterite and labradorite. Probably some cohenite is present in the sample. Analisys will be send to the buyer.

Size: 4 x 3.8 x 0.5 cm
Analyzed specimen with report
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RM1886   Meteorite of Chelyabinsk - Ordinary chondrite (LL5)

This is one of the fragments of the meteorite of Chelyabinsk. At 9:22 a.m. (local time) on February 15, 2013, a bright fireball was seen by numerous residents in parts of the Kurgan, Tyumen, Ekaterinburg and Chelyabinsk cities. This superbolide meteor descended at over 55,000 Km/h over the Ural Mountains, exploding at an altitude of 25-30 km.
These fragments are ordinary chondrite meteorites and contain 10% iron. The Chelyabinsk meteorite was later determined to come from the LL chondrite group (LL5). The majority of the stones are composed of a light-colored lithology with a typical chondritic texture. Chondrules (~63%) are readily delineated and set within a fragmental matrix. The chondrule glass is devitrified. The main phases are olivine and orthopyroxene. Rare grains of augite and clinobronzite are present. In this sample we can observe perfectly chondrules and fusion crust. Very representative and good sized sample (5.08 grams / 0.18 oz).
More info on the website of the Meteorical Society.

State/Prov/County: Chelyabinskaya oblast'  -  Date: 15 Feb 2013; 3:22 UT -  Coordinates: 54°49'N-61°07'E
Mass: >100 kg - Pieces: many - Class: LL5 - Shock stage: Moderated S4 - Weathering grade: W0

Size: 2.3 x 1.5 x 1.2 cm. (5.08 g.)
Found in 02/2013.
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RM1856   Spinel

This spinel crystal is complete all around and very richly faceted. It has an intense luster, characteristic of pocket-growth crystals that have never been covered by other rock or calcite infill which has to be removed with acid. This locality historically produced spinels of this caliber, and they came out 20 years and more ago and trickled to Western markets when the Berlin Wall fell. They stand as important spinels, not only as interesting locality classics. Sized spinels like this, from open pockets, are rare.

Size: 2.5 x 2.5 x 2.2 cm.
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RM1848   Ruthenium, Osmium 'Iridosmine'

These mix of crystals are showing hexagonal forms and analysis reports that they are related to Ruthenium crystals, with Osmium and Iridium. It is not easy to specify that if this or that crystal is Ru or Os, usually in this nuggets both elements could be present in different percentages. We will send analysis to the buyer.

Size: Mix 1.0 x 0.5 x 0.2 mm
Found in 2017
Elementos del Grupo del Platino / Platinum Group Elements
Analyzed specimen with report
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RM1839   Piemontite

Very curious specimen of piemontite, a rare Mn aluminosilicate near to Mn epidote, accompanied by braunite, in a shale matrix. One of its parts is cutted which allows to observe perfectly both braunite and piedmontite species. These specimens from the distant Kamchatka peninsula are not commonly available to collectors.

Size: 4.2 x 3.2 x 1.5 cm.
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RM1730   Lorenzenite

It is not very common to find specimens of lorenzenite, a rare sodium silicate titanate, of these Russian pegmatites. The piece shows some crystals with defined faces and edges, intense black and brilliance, some doubly ternminated. Very interesting specimen collected in this large agpaitic pegmatite body discovered in 1996 on the northern flank of the Umbozero mine on Alluaiv Mt. Intensely hydrothermally reworked, extremely Na-rich, CO2-rich and relatively Si-rich pegmatite. We will send analysis to the buyer.

Size: 4.6 x 4.0 x 3.6 cm.
Main crystal: 10 x 7 mm.
Analyzed specimen with report
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RM1672   Nakauriite with tremolite and talc

Nakauriite is a rare hydrated magnesium and copper carbonate, but old formula was Cu8(SO4)4(CO3)(OH)6·48H2O. The sulphate content, originally reported, seems to be questionable according to literature; the crystalline structure is unknown. Palenzona and Martinelli (2007) suggest a formula (Mg,Cu)x(CO3)y(OH)z·nH2O (x, y, z unknown). It appears as fibrous and nodular aggregates of bluish color embedded in the matrix of tremolite/talc. This specimen has an unusual size and is very rich. It comes from the abandoned chromite mines in Ufalei chromite deposits.
Palenzona, A. & Martinelli, A. (2007): La nakauriite del Monte Ramazzo, Genova. Rivista Mineralogica Italiana, 31(1), 48-51.

Size: 8.0 x 5.5 x 4.2 cm.
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RM1678   Isoferroplatinum

Isoproplatinum nugget showing cube shapes with cavities, some with geometric hoppered forms. Analysis show the iron content, which identifies it as this species. The central part of the Konder massif, formed by dunites, was weathered with the formation of a great depression. This depression is the bed of the famous alluvial placer that contains precious metals, among other minerals.

Size: 4 x 3 x 2 mm.
Main crystal: 0.26 g
Analyzed specimen with report
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